Bit of help needed with my maths

[Bonnox]

Yeah cheers guys I don't intend to ever let it run down to empty, I was just using the example to make the maths simpler to write up, Im led believe the same applies for charging batteries as well, that if they aren't fully topped up they have 'memory' so the full capacity of the battery can be lessened say if you only charge it to 70% each time then the battery thinks that 70% is actually full so 70% becomes the new 100% as it were! or is this only for the smaller batteries ?